4. Integration commands¶
Sometimes a software requires more configuration or processing than what is performed at installation time, otherwise it will not run properly.
This is especially true in cases where a daemon or library interoperates with third party extensions and needs to maintain a system wide cache whenever its extensions are installed or removed; system wide font caches are an example of this.
In these cases we use integration commands to ensure that a runtime is ready to run after all of its components have been staged.
Note
This example is distributed with BuildStream in the doc/examples/integration-commands subdirectory.
4.1. Overview¶
In this chapter, we’ll be exploring integration commands, which will be our first look at public data.
4.2. Project structure¶
4.2.1. project.conf and elements/base.bst¶
The project.conf and base stack stack element are configured in the
same way as in the previous chapter: Running commands.
4.2.2. elements/base/alpine.bst¶
kind: import
description: |
Alpine Linux base runtime
sources:
- kind: tar
url: alpine:integration-tests-base.v1.x86_64.tar.xz
ref: 3eb559250ba82b64a68d86d0636a6b127aa5f6d25d3601a79f79214dc9703639
#
# Run ldconfig in the libdir before running anything
#
public:
bst:
integration-commands:
- ldconfig "%{libdir}"
This is the same base/alpine.bst we’ve seen in previous chapters,
except that we’ve added an integration command.
This informs BuildStream that whenever the output of this element is
expected to run, this command should be run first. In this case we
are simply running ldconfig as a precautionary measure, to ensure
that the runtime linker is ready to find any shared libraries we may
have added to %{libdir}.
4.2.2.1. Looking at public data¶
The integration commands used here is the first time we’ve used any builtin public data.
Public data is a free form portion of an element’s configuration and is not necessarily understood by the element on which it is declared, public data is intended to be read by its reverse dependency elements.
This allows annotations on some elements to inform elements later in the dependency chain about details of its artifact, or to suggest how it should be processed.
4.2.3. elements/libhello.bst and elements/hello.bst¶
These are basically manual elements very similar to the ones we’ve seen in the previous chapter: Running commands.
These produce a library and a hello program which uses the library, we will consider these irrelevant to the topic and leave examination of their sources as an exercise for the reader.
4.3. Using the project¶
4.3.1. Build the hello.bst element¶
To build the project, run bst build in the following way:
user@host:~/integration-commands$ bst build hello.bst
[--:--:--][ ][ main:core activity ] STATUS Cache usage recomputed: 12K / infinity (0%)
[--:--:--][ ][ main:core activity ] START Build
[--:--:--][ ][ main:core activity ] START Loading elements
[00:00:00][ ][ main:core activity ] SUCCESS Loading elements
[--:--:--][ ][ main:core activity ] START Resolving elements
[00:00:00][ ][ main:core activity ] SUCCESS Resolving elements
[--:--:--][ ][ main:core activity ] START Resolving cached state
[00:00:00][ ][ main:core activity ] SUCCESS Resolving cached state
[--:--:--][ ][ main:core activity ] START Checking sources
[00:00:00][ ][ main:core activity ] SUCCESS Checking sources
BuildStream Version 1.3.0+1567.g067a0c6b.dirty
Session Start: Monday, 18-02-2019 at 20:39:50
Project: integration-commands (/home/user/integration-commands)
Targets: hello.bst
Cache Usage: 12K / infinity (0%)
User Configuration
Configuration File: /home/user/.config/buildstream.conf
Log Files: /home/user/.cache/buildstream/logs
Source Mirrors: /home/user/.cache/buildstream/sources
Build Area: /home/user/.cache/buildstream/build
Artifact Cache: /home/user/.cache/buildstream/artifacts
Strict Build Plan: Yes
Maximum Fetch Tasks: 10
Maximum Build Tasks: 4
Maximum Push Tasks: 4
Maximum Network Retries: 2
Pipeline
buildable f8700cb48e2c26e9a1d7f98c26edc90048217491282fa53b3e3d93f971633e0c base/alpine.bst
waiting 01431d85395431ae6ef96907a6416ea5e9d2c18862ba5428153c0ec16337e110 base.bst
waiting 3e55e626ff72b7f77d6efe2e5160ccd6d9269da817763d2a6ff1ef271b4b6cb0 libhello.bst
waiting 5430c9526aaed331b94d5073a8007a4d8be9cbdf8141166e47c4b7c0cda53cbc hello.bst
===============================================================================
[--:--:--][f8700cb4][build:base/alpine.bst ] START integration-commands/base-alpine/f8700cb4-build.4090.log
[--:--:--][f8700cb4][build:base/alpine.bst ] START Staging sources
[00:00:20][f8700cb4][build:base/alpine.bst ] SUCCESS Staging sources
[--:--:--][f8700cb4][build:base/alpine.bst ] START Caching artifact
[00:00:09][f8700cb4][build:base/alpine.bst ] SUCCESS Caching artifact
[00:00:35][f8700cb4][build:base/alpine.bst ] SUCCESS integration-commands/base-alpine/f8700cb4-build.4090.log
[--:--:--][01431d85][build:base.bst ] START integration-commands/base/01431d85-build.4095.log
[--:--:--][01431d85][build:base.bst ] START Caching artifact
[00:00:00][01431d85][build:base.bst ] SUCCESS Caching artifact
[00:00:00][01431d85][build:base.bst ] SUCCESS integration-commands/base/01431d85-build.4095.log
[--:--:--][3e55e626][build:libhello.bst ] START integration-commands/libhello/3e55e626-build.4100.log
[--:--:--][3e55e626][build:libhello.bst ] START Staging dependencies
[00:00:01][3e55e626][build:libhello.bst ] SUCCESS Staging dependencies
[--:--:--][3e55e626][build:libhello.bst ] START Integrating sandbox
[--:--:--][3e55e626][build:libhello.bst ] STATUS Running command
ldconfig "/usr/lib"
[00:00:00][3e55e626][build:libhello.bst ] SUCCESS Integrating sandbox
[--:--:--][3e55e626][build:libhello.bst ] START Staging sources
[00:00:00][3e55e626][build:libhello.bst ] SUCCESS Staging sources
[--:--:--][3e55e626][build:libhello.bst ] START Running build-commands
[--:--:--][3e55e626][build:libhello.bst ] STATUS Running command
make PREFIX="/usr"
[00:00:00][3e55e626][build:libhello.bst ] SUCCESS Running build-commands
[--:--:--][3e55e626][build:libhello.bst ] START Running install-commands
[--:--:--][3e55e626][build:libhello.bst ] STATUS Running command
make -j1 PREFIX="/usr" DESTDIR="/buildstream-install" install
[00:00:00][3e55e626][build:libhello.bst ] SUCCESS Running install-commands
[--:--:--][3e55e626][build:libhello.bst ] START Running strip-commands
[00:00:00][3e55e626][build:libhello.bst ] SUCCESS Running strip-commands
[--:--:--][3e55e626][build:libhello.bst ] START Caching artifact
[00:00:00][3e55e626][build:libhello.bst ] SUCCESS Caching artifact
[00:00:02][3e55e626][build:libhello.bst ] SUCCESS integration-commands/libhello/3e55e626-build.4100.log
[--:--:--][5430c952][build:hello.bst ] START integration-commands/hello/5430c952-build.4129.log
[--:--:--][5430c952][build:hello.bst ] START Staging dependencies
[00:00:01][5430c952][build:hello.bst ] SUCCESS Staging dependencies
[--:--:--][5430c952][build:hello.bst ] START Integrating sandbox
[--:--:--][5430c952][build:hello.bst ] STATUS Running command
ldconfig "/usr/lib"
[00:00:00][5430c952][build:hello.bst ] SUCCESS Integrating sandbox
[--:--:--][5430c952][build:hello.bst ] START Staging sources
[00:00:00][5430c952][build:hello.bst ] SUCCESS Staging sources
[--:--:--][5430c952][build:hello.bst ] START Running build-commands
[--:--:--][5430c952][build:hello.bst ] STATUS Running command
make PREFIX="/usr"
[00:00:00][5430c952][build:hello.bst ] SUCCESS Running build-commands
[--:--:--][5430c952][build:hello.bst ] START Running install-commands
[--:--:--][5430c952][build:hello.bst ] STATUS Running command
make -j1 PREFIX="/usr" DESTDIR="/buildstream-install" install
[00:00:00][5430c952][build:hello.bst ] SUCCESS Running install-commands
[--:--:--][5430c952][build:hello.bst ] START Running strip-commands
[00:00:00][5430c952][build:hello.bst ] SUCCESS Running strip-commands
[--:--:--][5430c952][build:hello.bst ] START Caching artifact
[00:00:00][5430c952][build:hello.bst ] SUCCESS Caching artifact
[00:00:02][5430c952][build:hello.bst ] SUCCESS integration-commands/hello/5430c952-build.4129.log
[00:00:40][ ][ main:core activity ] SUCCESS Build
Pipeline Summary
Total: 4
Session: 4
Fetch Queue: processed 0, skipped 4, failed 0
Build Queue: processed 4, skipped 0, failed 0
Observe in the build process above, the integration command declared on the
base/alpine.bst element is run after staging the dependency artifacts
into the build sandbox and before running any of the build commands, for
both of the libhello.bst and hello.bst elements.
BuildStream assumes that commands which are to be run in the build sandbox need to be run in an integrated sandbox.
Tip
Integration commands can be taxing on your overall build process, because they need to run at the beginning of every build which runtime depends on the element declaring them.
For this reason, it is better to leave out more onerous tasks if they are not needed at software build time, and handle those specific tasks differently later in the pipeline, before deployment.
4.3.2. Run the hello world program¶
Unlike the previous chapters, this hello world program takes an argument, we can invoke the program using bst shell:
user@host:~/integration-commands$ bst shell hello.bst -- hello pony
[--:--:--][ ][ main:core activity ] START Loading elements
[00:00:00][ ][ main:core activity ] SUCCESS Loading elements
[--:--:--][ ][ main:core activity ] START Resolving elements
[00:00:00][ ][ main:core activity ] SUCCESS Resolving elements
[--:--:--][ ][ main:core activity ] START Resolving cached state
[00:00:00][ ][ main:core activity ] SUCCESS Resolving cached state
[--:--:--][5430c952][ main:hello.bst ] START Staging dependencies
[00:00:01][5430c952][ main:hello.bst ] SUCCESS Staging dependencies
[--:--:--][5430c952][ main:hello.bst ] START Integrating sandbox
[--:--:--][5430c952][ main:hello.bst ] STATUS Running command
ldconfig "/usr/lib"
[00:00:00][5430c952][ main:hello.bst ] SUCCESS Integrating sandbox
[--:--:--][5430c952][ main:hello.bst ] STATUS Running command
hello pony
Hello pony
Here we see again, the integration commands are also used when preparing the shell to launch a command.
4.4. Summary¶
In this chapter we’ve observed how integration commands work, and we now know about public data, which plugins can read from their dependencies in order to influence their build process.